You need a file manger app, go to go to Goggle Playstore and download one of your choice, I tried a few astro etc but I am now using File Manger (by Rhythm Software) its basic but does what I want, ie attach usb open file manager and find your usb, and open. I also download MX player (Video Player) and when usb/dongle is attached open MX Player and any Videos on it will show up and your ready to go. Good Luck
